Synthetic and natural compounds that interact with human cytochrome P450 1A2 and implications in drug development.

Article Details

Citation

Wang B, Zhou SF

Synthetic and natural compounds that interact with human cytochrome P450 1A2 and implications in drug development.

Curr Med Chem. 2009;16(31):4066-218.

PubMed ID
19754423 [View in PubMed
]
Abstract

人类细胞色素P450 1 a2 (CYP1A2)的major CYPs in the liver ( approximately 13%) and metabolizes about 20% of clinically used drugs. CYP1A2 is a 515-residue protein with a molecular mass of 58,294 Dal. The recently published crystal structure of CYP1A2 in complex with alpha-naphthoflavone has showed a rather compact active site with a relatively small volume of the cavity of 375 A(3), which is 44.2% and 49.3% larger than that of CYP2A6 (260 A(3)) and CYP2E1 (190 A(3)), respectively. A series of residues in the substrate recognition regions of CYP1A2 (e.g. Arg108, Thr124, Thr223, Glu225, Phe226, Lys250, Arg251, Lys253, Asn312, Asp313, Glu318, Thr319, Asp320, Thr321, Val322, Leu382, Thr385, and Ile386) have been shown to play important roles in ligand-enzyme binding based on site-directed mutagenesis and homology modeling studies. Typical CYP1A2 substrates generally contain planar ring that can fit the narrow and planar active site of the enzyme, such as propranolol, clozapine, guanabenz, flutamide, imatinib, thalidomide, carbamazepine, lidocaine, theophylline, tacrine, tizanidine, zolpidem, riluzole, zileuton, and leflunomide. CYP1A2 is one of the major enzymes that bioactivate a number of procarcinogens including polycyclic aromatic hydrocarbons (e.g., benzo[a]pyrene), heterocyclic aromatic amines/amides (e.g. 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine), mycotoxins (e.g. aflatoxin B(1)) and some natural compounds such as aristolochic acids present in several Chinese herbal medicines. This enzyme also metabolizes several important endogenous compounds including retinols, melatonin, steroids, uroporphyrinogen and arachidonic acids. Like many of other CYPs, CYP1A2 is subject to induction and inhibition by a number of compounds. In particular, several therapeutic drugs including antofloxacin, carbamazepine, dihydralazine, furafylline, isoniazid, rofecoxib, clorgyline, thiabendazole, and zileuton are mechanism-based inhibitors of CYP1A2. Reversible and irreversible inhibition of by drugs CYP1A2 may provide an explanation for some clinical drug-drug interactions. Similar to CYP1A1 and 1B1, CYP1A2 is primarily regulated by the aromatic hydrocarbon receptor (AhR), a ligand-activated transcription factor and a basic helix-loop-helix protein belonging to the Per-Arnt-Sim family of transcription factors. CYP1A2 is polymorphic and a number of genetic mutations in CYP1A2 have been reported. It has been suggested that approximately 35 to 75% of the interindividual variability in CYP1A2 activity is due to genetic factors. Some of the mutations of CYP1A2 have been found to alter the clearance of drugs that are extensively metabolized by CYP1A2. Collectively, CYP1A2 plays a major role in drug metabolism, procarcinogen activation and some drug-drug interactions; it is important to identify whether a new drug is a substrate, inducer or inhibitor in drug development. This candidate selection might eventually lead to a less prominent role of this enzyme in the future for drug metabolism and minimize the potential for significant polymorphic metabolism in humans and drug-drug interactions when used in combination with CYP1A2 inhibitors.

DrugBank Data that Cites this Article

Drug Enzymes
Drug Enzyme Kind Organism Pharmacological Action Actions
Alosetron Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Inhibitor
Details
Carbamazepine Cytochrome P450 1A2 Protein Humans
Unknown
Inhibitor
Inducer
Details
Clozapine Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Flutamide Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Guanabenz Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Imatinib Cytochrome P450 1A2 Protein Humans
No
Substrate
Details
Isoniazid Cytochrome P450 1A2 Protein Humans
Unknown
Inhibitor
Details
Leflunomide Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Lidocaine Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Inhibitor
Details
Oxtriphylline Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Propranolol Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Rofecoxib Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Inhibitor
Details
Tacrine Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Theophylline Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Thiabendazole Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Inhibitor
Details
Tizanidine Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Zileuton Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Inhibitor
Details
Zolpidem Cytochrome P450 1A2 Protein Humans
Unknown
Substrate
Details
Drug Reactions
Reaction
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